1aa1f3bb5SGreg Kroah-Hartman // SPDX-License-Identifier: GPL-2.0
236e56a34SAlan Stern /*
3*9899aa5bSWei Ming Chen * drivers/usb/core/generic.c - generic driver for USB devices (not interfaces)
436e56a34SAlan Stern *
536e56a34SAlan Stern * (C) Copyright 2005 Greg Kroah-Hartman <gregkh@suse.de>
636e56a34SAlan Stern *
736e56a34SAlan Stern * based on drivers/usb/usb.c which had the following copyrights:
836e56a34SAlan Stern * (C) Copyright Linus Torvalds 1999
936e56a34SAlan Stern * (C) Copyright Johannes Erdfelt 1999-2001
1036e56a34SAlan Stern * (C) Copyright Andreas Gal 1999
1136e56a34SAlan Stern * (C) Copyright Gregory P. Smith 1999
1236e56a34SAlan Stern * (C) Copyright Deti Fliegl 1999 (new USB architecture)
1336e56a34SAlan Stern * (C) Copyright Randy Dunlap 2000
1436e56a34SAlan Stern * (C) Copyright David Brownell 2000-2004
1536e56a34SAlan Stern * (C) Copyright Yggdrasil Computing, Inc. 2000
1636e56a34SAlan Stern * (usb_device_id matching changes by Adam J. Richter)
1736e56a34SAlan Stern * (C) Copyright Greg Kroah-Hartman 2002-2003
1836e56a34SAlan Stern *
19b65fba3dSGreg Kroah-Hartman * Released under the GPLv2 only.
2036e56a34SAlan Stern */
2136e56a34SAlan Stern
2236e56a34SAlan Stern #include <linux/usb.h>
2327729aadSEric Lescouet #include <linux/usb/hcd.h>
24f13912d3SSaranya Gopal #include <uapi/linux/usb/audio.h>
2536e56a34SAlan Stern #include "usb.h"
2636e56a34SAlan Stern
plural(int n)27782da727SAlan Stern static inline const char *plural(int n)
28782da727SAlan Stern {
29782da727SAlan Stern return (n == 1 ? "" : "s");
30782da727SAlan Stern }
31782da727SAlan Stern
is_rndis(struct usb_interface_descriptor * desc)32ad55d71aSOle Andre Vadla Ravnas static int is_rndis(struct usb_interface_descriptor *desc)
33ad55d71aSOle Andre Vadla Ravnas {
34ad55d71aSOle Andre Vadla Ravnas return desc->bInterfaceClass == USB_CLASS_COMM
35ad55d71aSOle Andre Vadla Ravnas && desc->bInterfaceSubClass == 2
36ad55d71aSOle Andre Vadla Ravnas && desc->bInterfaceProtocol == 0xff;
37ad55d71aSOle Andre Vadla Ravnas }
38ad55d71aSOle Andre Vadla Ravnas
is_activesync(struct usb_interface_descriptor * desc)39ad55d71aSOle Andre Vadla Ravnas static int is_activesync(struct usb_interface_descriptor *desc)
40ad55d71aSOle Andre Vadla Ravnas {
41ad55d71aSOle Andre Vadla Ravnas return desc->bInterfaceClass == USB_CLASS_MISC
42ad55d71aSOle Andre Vadla Ravnas && desc->bInterfaceSubClass == 1
43ad55d71aSOle Andre Vadla Ravnas && desc->bInterfaceProtocol == 1;
44ad55d71aSOle Andre Vadla Ravnas }
45ad55d71aSOle Andre Vadla Ravnas
is_audio(struct usb_interface_descriptor * desc)46f13912d3SSaranya Gopal static bool is_audio(struct usb_interface_descriptor *desc)
47f13912d3SSaranya Gopal {
48f13912d3SSaranya Gopal return desc->bInterfaceClass == USB_CLASS_AUDIO;
49f13912d3SSaranya Gopal }
50f13912d3SSaranya Gopal
is_uac3_config(struct usb_interface_descriptor * desc)51f13912d3SSaranya Gopal static bool is_uac3_config(struct usb_interface_descriptor *desc)
52f13912d3SSaranya Gopal {
53f13912d3SSaranya Gopal return desc->bInterfaceProtocol == UAC_VERSION_3;
54f13912d3SSaranya Gopal }
55f13912d3SSaranya Gopal
usb_choose_configuration(struct usb_device * udev)56b5ea060fSGreg Kroah-Hartman int usb_choose_configuration(struct usb_device *udev)
57782da727SAlan Stern {
58782da727SAlan Stern int i;
59782da727SAlan Stern int num_configs;
60782da727SAlan Stern int insufficient_power = 0;
61782da727SAlan Stern struct usb_host_config *c, *best;
62782da727SAlan Stern
63c13b86a3SHindin Joseph if (usb_device_is_owned(udev))
64c13b86a3SHindin Joseph return 0;
65c13b86a3SHindin Joseph
66782da727SAlan Stern best = NULL;
67782da727SAlan Stern c = udev->config;
68782da727SAlan Stern num_configs = udev->descriptor.bNumConfigurations;
69782da727SAlan Stern for (i = 0; i < num_configs; (i++, c++)) {
70782da727SAlan Stern struct usb_interface_descriptor *desc = NULL;
71782da727SAlan Stern
72782da727SAlan Stern /* It's possible that a config has no interfaces! */
73782da727SAlan Stern if (c->desc.bNumInterfaces > 0)
74782da727SAlan Stern desc = &c->intf_cache[0]->altsetting->desc;
75782da727SAlan Stern
76782da727SAlan Stern /*
77782da727SAlan Stern * HP's USB bus-powered keyboard has only one configuration
78782da727SAlan Stern * and it claims to be self-powered; other devices may have
79782da727SAlan Stern * similar errors in their descriptors. If the next test
80782da727SAlan Stern * were allowed to execute, such configurations would always
81782da727SAlan Stern * be rejected and the devices would not work as expected.
82782da727SAlan Stern * In the meantime, we run the risk of selecting a config
83782da727SAlan Stern * that requires external power at a time when that power
84782da727SAlan Stern * isn't available. It seems to be the lesser of two evils.
85782da727SAlan Stern *
86782da727SAlan Stern * Bugzilla #6448 reports a device that appears to crash
87782da727SAlan Stern * when it receives a GET_DEVICE_STATUS request! We don't
88782da727SAlan Stern * have any other way to tell whether a device is self-powered,
89782da727SAlan Stern * but since we don't use that information anywhere but here,
90782da727SAlan Stern * the call has been removed.
91782da727SAlan Stern *
92782da727SAlan Stern * Maybe the GET_DEVICE_STATUS call and the test below can
93782da727SAlan Stern * be reinstated when device firmwares become more reliable.
94782da727SAlan Stern * Don't hold your breath.
95782da727SAlan Stern */
96782da727SAlan Stern #if 0
97782da727SAlan Stern /* Rule out self-powered configs for a bus-powered device */
98782da727SAlan Stern if (bus_powered && (c->desc.bmAttributes &
99782da727SAlan Stern USB_CONFIG_ATT_SELFPOWER))
100782da727SAlan Stern continue;
101782da727SAlan Stern #endif
102782da727SAlan Stern
103782da727SAlan Stern /*
104782da727SAlan Stern * The next test may not be as effective as it should be.
105782da727SAlan Stern * Some hubs have errors in their descriptor, claiming
106782da727SAlan Stern * to be self-powered when they are really bus-powered.
107782da727SAlan Stern * We will overestimate the amount of current such hubs
108782da727SAlan Stern * make available for each port.
109782da727SAlan Stern *
110782da727SAlan Stern * This is a fairly benign sort of failure. It won't
111782da727SAlan Stern * cause us to reject configurations that we should have
112782da727SAlan Stern * accepted.
113782da727SAlan Stern */
114782da727SAlan Stern
115782da727SAlan Stern /* Rule out configs that draw too much bus current */
1168d8479dbSSebastian Andrzej Siewior if (usb_get_max_power(udev, c) > udev->bus_mA) {
117782da727SAlan Stern insufficient_power++;
118782da727SAlan Stern continue;
119782da727SAlan Stern }
120782da727SAlan Stern
12125b01614SNikolay Yakimov /*
12225b01614SNikolay Yakimov * Select first configuration as default for audio so that
12325b01614SNikolay Yakimov * devices that don't comply with UAC3 protocol are supported.
12425b01614SNikolay Yakimov * But, still iterate through other configurations and
12525b01614SNikolay Yakimov * select UAC3 compliant config if present.
12625b01614SNikolay Yakimov */
12725b01614SNikolay Yakimov if (desc && is_audio(desc)) {
12825b01614SNikolay Yakimov /* Always prefer the first found UAC3 config */
12925b01614SNikolay Yakimov if (is_uac3_config(desc)) {
13025b01614SNikolay Yakimov best = c;
13125b01614SNikolay Yakimov break;
13225b01614SNikolay Yakimov }
13325b01614SNikolay Yakimov
13425b01614SNikolay Yakimov /* If there is no UAC3 config, prefer the first config */
13525b01614SNikolay Yakimov else if (i == 0)
13625b01614SNikolay Yakimov best = c;
13725b01614SNikolay Yakimov
13825b01614SNikolay Yakimov /* Unconditional continue, because the rest of the code
13925b01614SNikolay Yakimov * in the loop is irrelevant for audio devices, and
14025b01614SNikolay Yakimov * because it can reassign best, which for audio devices
14125b01614SNikolay Yakimov * we don't want.
14225b01614SNikolay Yakimov */
14325b01614SNikolay Yakimov continue;
14425b01614SNikolay Yakimov }
14525b01614SNikolay Yakimov
146ad55d71aSOle Andre Vadla Ravnas /* When the first config's first interface is one of Microsoft's
147ad55d71aSOle Andre Vadla Ravnas * pet nonstandard Ethernet-over-USB protocols, ignore it unless
148ad55d71aSOle Andre Vadla Ravnas * this kernel has enabled the necessary host side driver.
149c4e0b508SAlan Stern * But: Don't ignore it if it's the only config.
150ad55d71aSOle Andre Vadla Ravnas */
151c4e0b508SAlan Stern if (i == 0 && num_configs > 1 && desc &&
152c4e0b508SAlan Stern (is_rndis(desc) || is_activesync(desc))) {
153ad55d71aSOle Andre Vadla Ravnas #if !defined(CONFIG_USB_NET_RNDIS_HOST) && !defined(CONFIG_USB_NET_RNDIS_HOST_MODULE)
154782da727SAlan Stern continue;
155782da727SAlan Stern #else
156782da727SAlan Stern best = c;
157782da727SAlan Stern #endif
158782da727SAlan Stern }
159782da727SAlan Stern
160782da727SAlan Stern /* From the remaining configs, choose the first one whose
161782da727SAlan Stern * first interface is for a non-vendor-specific class.
162782da727SAlan Stern * Reason: Linux is more likely to have a class driver
163782da727SAlan Stern * than a vendor-specific driver. */
164782da727SAlan Stern else if (udev->descriptor.bDeviceClass !=
165782da727SAlan Stern USB_CLASS_VENDOR_SPEC &&
16662f9cfa3SAlan Stern (desc && desc->bInterfaceClass !=
167782da727SAlan Stern USB_CLASS_VENDOR_SPEC)) {
168782da727SAlan Stern best = c;
169782da727SAlan Stern break;
170782da727SAlan Stern }
171782da727SAlan Stern
172782da727SAlan Stern /* If all the remaining configs are vendor-specific,
173782da727SAlan Stern * choose the first one. */
174782da727SAlan Stern else if (!best)
175782da727SAlan Stern best = c;
176782da727SAlan Stern }
177782da727SAlan Stern
178782da727SAlan Stern if (insufficient_power > 0)
179782da727SAlan Stern dev_info(&udev->dev, "rejected %d configuration%s "
180782da727SAlan Stern "due to insufficient available bus power\n",
181782da727SAlan Stern insufficient_power, plural(insufficient_power));
182782da727SAlan Stern
183782da727SAlan Stern if (best) {
184782da727SAlan Stern i = best->desc.bConfigurationValue;
185b1f0a34cSMatthew Wilcox dev_dbg(&udev->dev,
186782da727SAlan Stern "configuration #%d chosen from %d choice%s\n",
187782da727SAlan Stern i, num_configs, plural(num_configs));
188782da727SAlan Stern } else {
189782da727SAlan Stern i = -1;
190782da727SAlan Stern dev_warn(&udev->dev,
191782da727SAlan Stern "no configuration chosen from %d choice%s\n",
192782da727SAlan Stern num_configs, plural(num_configs));
193782da727SAlan Stern }
194782da727SAlan Stern return i;
195782da727SAlan Stern }
196b7945b77SValentina Manea EXPORT_SYMBOL_GPL(usb_choose_configuration);
197782da727SAlan Stern
__check_for_non_generic_match(struct device_driver * drv,void * data)19828157b8cSBastien Nocera static int __check_for_non_generic_match(struct device_driver *drv, void *data)
19988b7381aSBastien Nocera {
20088b7381aSBastien Nocera struct usb_device *udev = data;
20188b7381aSBastien Nocera struct usb_device_driver *udrv;
20288b7381aSBastien Nocera
20388b7381aSBastien Nocera if (!is_usb_device_driver(drv))
20488b7381aSBastien Nocera return 0;
20588b7381aSBastien Nocera udrv = to_usb_device_driver(drv);
20688b7381aSBastien Nocera if (udrv == &usb_generic_driver)
20788b7381aSBastien Nocera return 0;
2080942d59bSBastien Nocera return usb_driver_applicable(udev, udrv);
20988b7381aSBastien Nocera }
21088b7381aSBastien Nocera
usb_generic_driver_match(struct usb_device * udev)21188b7381aSBastien Nocera static bool usb_generic_driver_match(struct usb_device *udev)
21288b7381aSBastien Nocera {
21377419aa4SBastien Nocera if (udev->use_generic_driver)
21477419aa4SBastien Nocera return true;
21577419aa4SBastien Nocera
21688b7381aSBastien Nocera /*
21788b7381aSBastien Nocera * If any other driver wants the device, leave the device to this other
21888b7381aSBastien Nocera * driver.
21988b7381aSBastien Nocera */
22028157b8cSBastien Nocera if (bus_for_each_drv(&usb_bus_type, NULL, udev, __check_for_non_generic_match))
22188b7381aSBastien Nocera return false;
22288b7381aSBastien Nocera
22388b7381aSBastien Nocera return true;
22488b7381aSBastien Nocera }
22588b7381aSBastien Nocera
usb_generic_driver_probe(struct usb_device * udev)226ef0f7d18SBastien Nocera int usb_generic_driver_probe(struct usb_device *udev)
22736e56a34SAlan Stern {
228782da727SAlan Stern int err, c;
229782da727SAlan Stern
230782da727SAlan Stern /* Choose and set the configuration. This registers the interfaces
231782da727SAlan Stern * with the driver core and lets interface drivers bind to them.
232782da727SAlan Stern */
233c13b86a3SHindin Joseph if (udev->authorized == 0)
234f8a37464SInaky Perez-Gonzalez dev_err(&udev->dev, "Device is not authorized for usage\n");
235f8a37464SInaky Perez-Gonzalez else {
236b5ea060fSGreg Kroah-Hartman c = usb_choose_configuration(udev);
237782da727SAlan Stern if (c >= 0) {
238782da727SAlan Stern err = usb_set_configuration(udev, c);
239e9e88fb7SAlan Stern if (err && err != -ENODEV) {
240782da727SAlan Stern dev_err(&udev->dev, "can't set config #%d, error %d\n",
241782da727SAlan Stern c, err);
242782da727SAlan Stern /* This need not be fatal. The user can try to
243782da727SAlan Stern * set other configurations. */
244782da727SAlan Stern }
245782da727SAlan Stern }
246f8a37464SInaky Perez-Gonzalez }
247782da727SAlan Stern /* USB device state == configured ... usable */
248782da727SAlan Stern usb_notify_add_device(udev);
249782da727SAlan Stern
25036e56a34SAlan Stern return 0;
25136e56a34SAlan Stern }
252782da727SAlan Stern
usb_generic_driver_disconnect(struct usb_device * udev)253ef0f7d18SBastien Nocera void usb_generic_driver_disconnect(struct usb_device *udev)
25436e56a34SAlan Stern {
255782da727SAlan Stern usb_notify_remove_device(udev);
256782da727SAlan Stern
25736e56a34SAlan Stern /* if this is only an unbind, not a physical disconnect, then
25836e56a34SAlan Stern * unconfigure the device */
25901d883d4SAlan Stern if (udev->actconfig)
2603f141e2aSAlan Stern usb_set_configuration(udev, -1);
26136e56a34SAlan Stern }
26236e56a34SAlan Stern
263782da727SAlan Stern #ifdef CONFIG_PM
264782da727SAlan Stern
usb_generic_driver_suspend(struct usb_device * udev,pm_message_t msg)265ef0f7d18SBastien Nocera int usb_generic_driver_suspend(struct usb_device *udev, pm_message_t msg)
266782da727SAlan Stern {
267b6f6436dSAlan Stern int rc;
268b6f6436dSAlan Stern
269686314cfSAlan Stern /* Normal USB devices suspend through their upstream port.
270686314cfSAlan Stern * Root hubs don't have upstream ports to suspend,
271686314cfSAlan Stern * so we have to shut down their downstream HC-to-USB
272686314cfSAlan Stern * interfaces manually by doing a bus (or "global") suspend.
273b6f6436dSAlan Stern */
274686314cfSAlan Stern if (!udev->parent)
27565bfd296SAlan Stern rc = hcd_bus_suspend(udev, msg);
2765ad4f71eSAlan Stern
27764627388SZhengjun Xing /*
27864627388SZhengjun Xing * Non-root USB2 devices don't need to do anything for FREEZE
27964627388SZhengjun Xing * or PRETHAW. USB3 devices don't support global suspend and
28064627388SZhengjun Xing * needs to be selectively suspended.
28164627388SZhengjun Xing */
28264627388SZhengjun Xing else if ((msg.event == PM_EVENT_FREEZE || msg.event == PM_EVENT_PRETHAW)
28364627388SZhengjun Xing && (udev->speed < USB_SPEED_SUPER))
2845ad4f71eSAlan Stern rc = 0;
285686314cfSAlan Stern else
28665bfd296SAlan Stern rc = usb_port_suspend(udev, msg);
2875ad4f71eSAlan Stern
2887794f486SAlan Stern if (rc == 0)
2897794f486SAlan Stern usbfs_notify_suspend(udev);
290b6f6436dSAlan Stern return rc;
291782da727SAlan Stern }
292782da727SAlan Stern
usb_generic_driver_resume(struct usb_device * udev,pm_message_t msg)293ef0f7d18SBastien Nocera int usb_generic_driver_resume(struct usb_device *udev, pm_message_t msg)
294782da727SAlan Stern {
295b6f6436dSAlan Stern int rc;
296b6f6436dSAlan Stern
297686314cfSAlan Stern /* Normal USB devices resume/reset through their upstream port.
298686314cfSAlan Stern * Root hubs don't have upstream ports to resume or reset,
299686314cfSAlan Stern * so we have to start up their downstream HC-to-USB
300686314cfSAlan Stern * interfaces manually by doing a bus (or "global") resume.
301686314cfSAlan Stern */
302686314cfSAlan Stern if (!udev->parent)
30365bfd296SAlan Stern rc = hcd_bus_resume(udev, msg);
3040458d5b4SAlan Stern else
30565bfd296SAlan Stern rc = usb_port_resume(udev, msg);
3067794f486SAlan Stern
3077794f486SAlan Stern if (rc == 0)
3087794f486SAlan Stern usbfs_notify_resume(udev);
309b6f6436dSAlan Stern return rc;
310782da727SAlan Stern }
311782da727SAlan Stern
312782da727SAlan Stern #endif /* CONFIG_PM */
313782da727SAlan Stern
3148bb54ab5SAlan Stern struct usb_device_driver usb_generic_driver = {
31536e56a34SAlan Stern .name = "usb",
31688b7381aSBastien Nocera .match = usb_generic_driver_match,
317ef0f7d18SBastien Nocera .probe = usb_generic_driver_probe,
318ef0f7d18SBastien Nocera .disconnect = usb_generic_driver_disconnect,
319782da727SAlan Stern #ifdef CONFIG_PM
320ef0f7d18SBastien Nocera .suspend = usb_generic_driver_suspend,
321ef0f7d18SBastien Nocera .resume = usb_generic_driver_resume,
322782da727SAlan Stern #endif
32301d883d4SAlan Stern .supports_autosuspend = 1,
32436e56a34SAlan Stern };
325